1 billion cows vs. Lab-grown meat

It’s estimated that there are about 1 billion cows, 1.2 billion sheep and 23 billion chickens in the world [1,2,3]. What if we could make meat without the need for all these animals?

This would certainly save a lot of greenhouse gas emission: the livestock sector contributes about 14.5% of global emissions caused by humans [4]. It is partly for this reason that scientists are trying to grow meat in the lab [5].

To grow animal muscle, you need to start with ‘stem cells’ – these are special cells that can divide and specialise into different types of cells [5,6]. The stem cells can be obtained either from an animal embryo (a group of cells that eventually develop into an animal [7]), or they can be taken from the muscle of an adult animal [5]. That way, fewer animals are needed than for conventional meat production – one company claims that a single small sample of tissue from a cow can produce 80,000 quarter pounder beef burgers [8].

The stem cells can be grown first in a small dish, and then in a larger tank of cells where they replicate [5]. The cells are later transferred to a frame to enable them to grow into the shape of muscle fibres [5]. The amount of fat and other nutrients in the meat can be controlled [5].

Although meat can be grown in a lab by this process in small amounts, scaling up the process is proving to be a challenge [5].

Estimates find that lab-grown meat has lower greenhouse gas emissions, land use and water use than conventional beef, but similar to that of poultry [5,9]. Emissions are higher than for plant-based protein-rich crops like peas and beans, but more similar to processed vegetarian meat substitutes [5,9].

One concern with artificial meat is that it will, at least initially, be more expensive than plant-based meat substitutes [5]. Therefore, it would need to be more tasty, nutritious or have some other benefit so that people are willing to pay a little extra [5].